As unconventional gas grows and as the terms of international gas trade evolve and become more flexible (for example with a large increase in LNG trade), the IEA anticipate that this will put continued pressure on conventional gas suppliers and on traditional oil-linked pricing mechanisms for gas, or oil-indexing. The development of an Asian gas trading hub, for example, could markedly improve that region's competitiveness. The development of Europe's sizeable resources of unconventional gas could play a role in bolstering and diversifying sources of supply. That would also put pressure on conventional suppliers and oil-indexing, but our outlook for European shale gas is rather pessimistic. That's because of a host of issues including sub-soil ownership rights, geological particularities, population density, and of course public acceptance of fracking.